Data Sufficiency

n is a positive integer.Is 30 a factor of n ??
A. n^2 is divisible by 30.
B. 30 is a factor of 2n.

My answer is E, please lemme know whether this is right?

1. I'd like to start off by pointing out that 30 has no repeating prime factors (i.e., it's different from 8 = 2*2*2): 30 = 2*3*5. This is why I believe that if n^2 is divisible by 30, then n will also be divisible by 30. This happens because in n^2 we basically "repeat" all the prime factors in n.

A counterexample would be for that 8 I pointed out: 4^2 will be divisible by 8 but 4 is not
So 1 is sufficient to establish that n is indeed divisible by 30.

2 is not enough. Take n = 15 for instance: 30 is a factor of 2n but you can't say that n is divisible by 30. However, if you take n = 60, then 30 is a factor of 2n and n is divisible by 30.

IMHO, the answer is A.

The answer is A.

stmt 2 says 30 is a factor of 2n
say n=15 then 30 is not a factor of n.

stmt 1 says :

n^2 is dvided by 30.

or n^2 has factors in the form of 2^a* 3^b*5^c*x^y etc.

no matter what the value of a,b,c, n will be having factors square root of them and hence divisible by 30.

Hence A wins.